Nuclear spin polarization transfer across an organic-semiconductor interface

Nuclear spin polarization transfer across an organic-semiconductor interface

Motivated by Tycko’s proposal to harness optically pumped nuclear spin polarization for the enhancement of nuclear magnetic resonance ~NMR! signals from biological macromolecules, we investigate the transfer of thermal nuclear spin polarization between H or F in an organic overlayer and P at the surface of micron-sized InP particles by Hartmann–Hahn cross polarization. Comparison with analytic ...

Dynamic nuclear spin polarization in an all-semiconductor spin injection device with (Ga,Mn)As/n-GaAs spin Esaki diode

Transfer of Orbital Angular Momentum Polarization to Nuclear Spin Polarization in External Fields. - a Theoretical Study

The effect of an external magnetic field on the transfer of electron shell to nuclear spin polarization is studied under the condition that the beam traverses the field region adiabatically. We find that the modification of the nuclear spin orientation'is partially caused by a transfer of electronic alignment. Such an effect would not occur under sudden passage conditions. R&sum&.L'effet d'un c...

Spin control of drifting electrons using local nuclear polarization in ferromagnet-semiconductor heterostructures.

We demonstrate methods to locally control the spin rotation of moving electrons in a GaAs channel. The Larmor frequency of optically injected spins is modulated when the spins are dragged through a region of spin-polarized nuclei created at a MnAs/GaAs interface. The effective field created by the nuclei is controlled either optically or electrically using the ferromagnetic proximity polarizati...

Dynamic nuclear polarization by electrical spin injection in ferromagnet-semiconductor heterostructures.

Electrical spin injection from Fe into AlxGa1-xAs quantum well heterostructures is demonstrated in small (<500 Oe) in-plane magnetic fields. The measurement is sensitive only to the component of the spin that precesses about the internal magnetic field in the semiconductor. This field is much larger than the applied field and depends strongly on the injection current density. Details of the obs...